-er bbb bbe bbg bbi bbr bbt bbx be- beb bee beg bei ber bet bex bgb bge bgg bgi bgr bgt bgx bi- bib bie big bii bir bit bix brb bre brg bri brr brt brx btb bte btg bti btr btt btx bxb bxi bxx ebb ebe ebg ebi ebr ebt ebx eeb eee eeg eer eet eex egb ege egg egi egr egt egx eib eie eig eii eir eit eix erb ere erg eri err ert etb ete etg eti etr ett etx ex- exe exi exr ext exx gbe gbg gbi gbr gbt gbx ge- geb gee geg gei ger get gex ggb ggg ggi ggr ggt gib gie gig gii gir git grb gre grg gri grr grt grx gtb gte gtg gti gtr gtt gtx gxt ibb ibe ibg ibi ibr ibt ibx ie- iee ieg iei ier iet iex igb ige igg igi igr igt iib iie iii iir iit iix ir- irb ire irg iri irr irt irx itb ite itg iti itt itx ixe ixi rbb rbe rbg rbi rbr rbt rbx re- reb ree reg rei rer ret rex rgb rge rgg rgi rgr rgt rgx rib rie rig rii rir rit rix rrb rrg rri rrr rrt rtb rte rtg rti rtr rtt rtx rxr t-x tbb tbe tbg tbi tbr tbt te- teb tee teg tei ter tet tex tgb tge tgg tgi tgr tgt tib tie tig tii tir tit tix trb tre trg tri trr trt trx ttb tte ttg tti ttr ttt ttx txe txi txt xbe xbr xbx xee xeg xer xet xex xge xgi xie xii xit xix xrt xrx xti xtr xtx xxi xxx